Magnetic head having an antistripping layer for preventing a magnetic layer from stripping

ABSTRACT

By inserting a first antistripping layer comprising a first non-magnetic layer  22  and a first conductive layer  23  between a first magnetic layer  16  and a magnetic separation layer  13,  adhesion between the first conductive layer  23  and the magnetic separation layer  13  is improved to prevent the first magnetic layer  16  from stripping. In addition, by inserting a second antistripping layer comprising a second non-magnetic layer  24  and a second conductive layer  25  between a second magnetic layer  21  and a magnetic gap layer  17,  adhesion between the second conductive layer  24  and the magnetic gap layer  17  is improved to prevent the second magnetic layer  25  from stripping.

CROSS-REFERENCES TO RELATED APPLICATIONS

[0001] This is a continuation-in-part application of U.S. applicationSer. No. 09/672,597, filed on Sep. 28, 2000, now abandoned.

BACKGROUND OF THE INVENTION

[0002] This invention relates to a magnetic head for recordinginformation on a magnetic recording medium, to a method of manufacturingthe magnetic head, and to a magnetic storage unit using the magnetichead.

[0003] A magnetic recording medium is disclosed, for example, inJapanese Unexamined Patent Publication of Tokka:. No. Hei 9-138,930 (orJP-A 9-138930). JP-A 9-138930 provides a magnetic recording medium toobtain high magnetic characteristics and to improve adhesion propertybetween a substrate and a base layer. According to JP-A 9-138930, firstbase layers, second base layers magnetic layers and lubricant layers aresuccessively formed on a substrate. Among the base layers, the firstbase layers formed near the substrate have higher specific heat thanthat of the second base layers deposited far from the substrate.Thereby, the temperature in orientation controlling layers and magneticlayers can be enough raised without increasing the temperature in theinside and surface of the substrate so much. Thereby, adhesion propertybetween the first base layers and the substrate can be improved, whichprevents peeling of the first base layers.

[0004] The magnetic storage units may be a magnetic disk drive. In themagnetic disk drive, data is written and read by thin film magnetictransducers called “magnetic heads” which are supported over a surfaceof the magnetic recording medium or disk while it is rotated at a highspeed. The magnetic head are supported by a thin cushion of air (an “airbearing”) produced by the disk's high rotational speed.

[0005] With miniaturization and large-capacity in the magnetic storageunit, a volume per one bit recorded on the magnetic recording mediumdrastically becomes small. In the manner which is well known in the art,there is a magnetoresistive (MR) head to detect, as a large read output,a magnetic signal generated from a microscopic bit.

[0006] Inasmuch as the MR head is exclusively used for reading, the MRhead is used as a merged MR head which employs the MR head and aninductive (ID) head for writing in combination. Such as a merged MR headis disclosed, for example, in U.S. Pat. No. 5,438,747, JapaneseUnexamined Patent Publication of Tokkai No. Hei 8-212,512 (or JP-A8-212512), and Japanese Granted Patent Publication of No. 2,821,456 (orJP-B 2821456) which corresponds to U.S. patent application Ser. No.09/108,252).

[0007] U.S. Pat. No. 5,439,747 provides a merged MR head havingvertically aligned sidewalls so as to minimize side-fringing and improveoff-track performance. When a magnetic recording disk is rotated, a thinfilm merged MR head, mounted on a slider, is supported above a surfaceof the magnetic recording disk by a thin layer of air called an “airbearing”. The merged MR head includes an MR read head and an IR writehead. The bottom surface of the slider and the merged MR head are in theplane of an air bearing surface (ABS) of the slider. The MR read headincludes a magnetoresistive element MR which is sandwiched between firstand second gap layers, the gap layers in turn being sandwiched betweenfirst and second shield layers. The first and second gap layers arecollectively called a magnetic separation layer. In a merged MR head,the second shield layer of the MR read head also serves as the bottompole piece for the IR write head. The bottom pole piece is called afirst or lower magnetic layer. The IR write head has a pole tip regionwhich is located between the air bearing surface (ABS) and a zero throatlevel and a yoke or back region which extends back from the zero throatlevel to and including a back gap The IR write head includes the bottompole piece and a top pole piece. The top pole piece is called a secondor upper magnetic layer. The bottom pole piece comprises the secondshield layer of the MR read head. Each pole piece also has a back layerportion which is located in the back region, the back layer portions ofthe pole pieces being magnetically connected at the back gap (BG). Thebottom pole piece includes a pole tip structure which is located in thepole tip region between the ABS and the zero throat level. This pole tipstructure includes a bottom pole tip element and a top pole tip element.The top pole piece includes a pole tip structure which is located in thepole tip region between the ABS and the zero throat level. This pole tipstructure includes a top pole tip element. The pole tip elements areintegrally formed from second shield of the MR read head. A pole gaplayer (G) is sandwiched between the pole tip elements.

[0008] JP-A 8-212512 discloses a magnetic head for a high recordingdensity in a high-frequency region. Specifically, JP-A 8-212512discloses a recording and reproducing separated type head whichcomprises an inductive (IR) write head, a magnetoresistive (MR) readhead, and a shield member for preventing the MR read head from beingconfused due to a leakage magnetic field. The MR read head comprises alower shield layer formed on a substrate, a magnetoresistance effectlayer, electrodes, and an upper shield layer. The IR write headcomprises a lower magnetic layer, a write coil, and an upper magneticlayer.

[0009] JP-B 2821456 discloses a merged MR head which comprises a MR readhead and an IR write head. The IR write head comprises a lower magneticlayer, an insulating layer formed on the lower magnetic layer, a writecoil enclosed with the insulating layer, and an upper magnetic layerformed on the insulating layer. The write coil is a patterned conductivelayer. The MR read head comprises a lower shield layer, a gap layerformed on the lower shield layer, a magneto-resistance effect elementsandwiched in the gap layer at one end thereof, an upper shield layerformed on the gap layer. The lower magnetic layer is the upper shieldlayer itself.

[0010] Recently, a giant magnetoresistive (GMR) read head is madepracticable. The MM read head uses a GMR effect which is capable ofrealizing a drastic high output in comparison with the MR read head. TheGMR read head generally uses a spin valve effect. The “spin valveeffect” is a phenomenon where a variation of resistance corresponds to acosine between magnetic directions of two adjacent magnetic layers andthereby a large variation of resistance is obtained by a smalloperational magnetic field. Such a GMR read head using the spin valveeffect is disclosed, for example, in Japanese Unexamined PatentPublications of Tokkai No. Hei 10-162,322 (or JP-A 10-162322) and TokkaiNo. Hei 11-16,120 (or JP-A 11-16120).

[0011] JP-A 10-162322 provides a merged GMR head that realizessimultaneously the magnetizing direction of the magnetization fixinglayer of a spin valve element and the magnetic anisotropic direction ofa magnetic shield or a recording magnetic pole, and that can secure astable operation of a magnetoresistence effect (MR) read head part andan indudtive (ID) write head part. The merged GMR head disclosed in JP-A10-162,322 is equipped with an MR read head part having a reproducingfunction and an ID write head part recording prescribed information on amagnetic recording medium with a magnetic gap part. An MR element isconstituted of a center area and end areas. The center area consists ofspin valve elements and senses a media magnetic field. The end areassupply a bias magnetic field and an electric current. The other magneticpole of the ID write head part is constituted of two kinds of laminatedmagnetic films having a different degree of saturation magnetization.The saturation magnetization of the magnetic film close to a magneticgap inside each magnetic film is set to be larger than that of themagnetic film away from the magnetic gap.

[0012] JP-A 11-16120 provides a magnetic domain structure which may beoptimized even without the execution of the head treatment. JP-A11-16120 discloses a recording and reproducing separated-type head usinga thin film magnetic head. The recording and reproducing separated-typehead comprises a reproducing or read head and a recording or write head.The reproducing head comprises a magnetoresistence effect film which issandwiched between first and second shield layers. In addition, thesecond shield layer serves as a lower magnetic pole of the recordinghead. The recording head comprises the lower magnetic pole, a shieldlayer sandwiching a coil, and an upper magnetic pole. Themagnetoresistence effect film is a spin valve film.

[0013] The GMR read head is practically used at a high-density recordingarea having a recording density of 3 gigabits/inch² or more. At arecording area having a recording density less than 3 gigabits/inch², itis possible to sufficiently cover by a conventional MR head usingmagnetic anisotropy. That is, a practically significant GMR read headrealizes a high-density recording and reproducing of 3 gigabits/inch² ormore. Accordingly, a magnetic storage apparatus constructed using theGMR head is a high-density recording and reproducing apparatus of 3gigabits/inch² or more.

[0014] On the other hand, in the ID write head carrying a recordingfunction to a magnetic recording medium, an improvement of ahigh-density recording performance is always requested with developmentof the GMR read head. In particularly, a high coercive force to themagnetic recording medium is indispensable to carry out a high-densityrecording. This is to minimize a transition length of a magnetizingrecorded in the magnetic recording medium with improvement of arecording density and to stably hold the magnetizing although a lengthof the magnetizing per one bit is shortened. For this purpose,development for the ID write head to enlarge a recording magnetic fieldis energetically advanced so as to record the magnetic recording mediumof a high coercive force which is suitable for the high-densityrecording.

[0015] Now, with considerations of convenience and low cost in amanufacturing process of the magnetic head, it is effective that amagnetic material is formed by plating. In the plating, it is possibleto obtain a desired pattern by forming a photo-resist frame where ashape of magnetic poles (first and second magnetic layers) ispreliminarily bored and by growing a plating layer within thephoto-resist frame. The first and the second magnetic layers are calledlower and upper magnetic layers, respectively. Inasmuch as this methodis convenience and low cost, this method presently becomes a standardmanufacturing method of a thin-film magnetic head.

[0016] Various thin magnetic films suitable for magnetic layers arealready known. By way of example, the above-mentioned JP-A 11-16120discloses a two-layered film comprising a nickel-iron (NiFe) alloy as anessential element. The two-layered film consists of a first magneticsub-layer having a high saturation magnetic flux density and a secondmagnetic sub-layer having a low magnetostriction constant. The first andthe second magnetic sub-layers are formed by changing a current densityby using a flame plating method on an insulating film.

[0017] U.S. Pat. No. 4,661,216 discloses an electoplating bathcomposition for electroplating a coating of a cobalt-nickel-iron(CoNiFe) alloy with low coercivity, high saturation magnetization (4πMs), and 0 or slightly negative magnetization (λs) for use in thin filmheads for reading and writing. The CoNiFe electroplating bathcomposition disclosed in U.S. Pat. No. 4,661,216 includes a stressreliving agent such as saccharin.

[0018] Japanese Unexamined Patent Publication of Tokkai No. Hei6-346,202 or JP-A 6-346202 discloses a soft magnetic alloy having highBs, low Hc, and high μ. According to JP-A 6-346202, essential componentsof this soft magnetic alloy are constituted of iron (Fe), cobalt (Co),and nickel (Ni). In the formula of Fe_(x)Co_(y)Ni_(z), the atomic ratioof each element in these essential components is expressed by0.1≦x≦0.55, 0.20≦y≦0.85, 0.05≦z≦0.35 and x+y+z=1. The soft magneticalloy is substantially constituted of a face-centered cubic crystalsingle phase. In the case the peak intensity of the (200) plane and thatof the (ill) plane in the X-ray analysis are respectively defined asI(200) and I(111), I(200)/I(111)≧0.25 is regulated. Furthermore, theabsolute value of the saturation magnetostrictoin value (λs) isregulated to 5×10⁻⁶ or below. In this way, the λs can substantially beregulated to zero even in the compositional range by which high Bs canbe obtained.

[0019] The above-mentioned JP-B 2821456 also discloses a soft magneticfilm suitable for the first and the second magnetic layer. The softmagnetic film is a Co—Ni—Fe plating film formed with a plating bathincluding no addition agent such as saccharin to obtain a pure filmhaving a sulfur content of 0.1% by weight or less. Such a soft magneticfilm has a magnetostrictive constant reduced up to a practical level, anextremely high saturation magnetic flux density (Bs) of 1.9-2.2 T, andan extremely small coercive force of 199 A/m or less. The soft magneticfilm is called a high-Bs soft magnetic film.

[0020] However, when the first (lower) and the second (upper) magneticlayers are formed using the high-Bs soft magnetic film, problems ariseas follows:

[0021] {circle over (1)} stripping or peeling occurs in the first andthe second magnetic layers;

[0022] {circle over (2)} cracks occur in a step cover (SC) film which isa boundary face between first and second insulating layers covering thewrite coil; and

[0023] {circle over (3)} cracks occur in a frame resist on forming thehigh-Bs soft magnetic film, the plating film grows along the cracks, andthen abnormality in shape or shape anomaly occurs in the first and thesecond magnetic layers.

SUMMARY OF THE INVENTION

[0024] It is therefore an object of this invention to provide a magnetichead suitable for a high recording density by resolving various problemswhich occur in a case where high-Bs soft magnetic films are applied tofirst and second magnetic layers.

[0025] It is another object of this invention to provide a manufacturingprocess suitable for the above-mentioned magnetic head.

[0026] It is still another object of this invention to provide amagnetic storage device with the above-mentioned magnetic head.

[0027] Other objects of this invention will become clear as thedescription proceeds.

[0028] The present inventors discovered that stripping or the like occurbecause the high-Bs soft magnetic film has a large stress of about200MPa and that the high-Bs soft magnetic film has an enlarged adhereforce and a reduced stress by inserting a non-magnetic layer under thehigh-Bs soft magnetic film. This invention is made based on thisknowledge.

[0029] That is, this invention improves a magnetic head comprising asubstrate having a principal surface, a first magnetic layer formed onthe principal surface of the substrate, a recording gap layer formed onthe first magnetic layer, an insulating layer formed on the recordinggap layer, a write coil enclosed with and insulated by the insulatinglayer, and a second magnetic layer. This improvement is that a firstantistripping layer is provided under the first magnetic layer and/orthat a second antistripping layer is provided under the second magneticlayer. The first antistripping layer may comprise a first conductivelayer formed under the first magnetic layer and a first non-magneticlayer formed under the first conductive layer. The second antistrippinglayer may comprise a second conductive layer formed under the secondmagnetic layer and a second non-magnetic layer formed under the secondconductive layer.

[0030] The conductive layer serves as an electrode on forming themagnetic layer by electroplating. By inserting the nonmagnetic layerbetween the conductive layer and the substrate or the insulating layer,adhesion between the conductive layer and the substrate or theinsulating layer is improved. By improving this adhesion, stripping ofthe conductive layer caused by a large stress of the magnetic layer. Asa result, adhesion of the magnetic layer increases.

[0031] The non-magnetic layer may preferably comprise a lamina made of anon-magnetic material (metal) of titanium (Ti) because of largeadhesion. However, the non-magnetic layer may comprise a lamina made ofmetal selected from the group consisting essentially of tantalum (Ta),chromium (Cr) , yttrium (Y), zirconium (Zr), hafnium (Hf), vanadium (V),niobium (Nb), molybdenum (Mo), and tungsten (W). When the non-magneticlayer is made of titanium, the first non-magnetic layer may preferablyhave a thickness between 2 nm and 10 nm, both inclusive and the secondnonmagnetic layer may preferably have a thickness between 10 nm and 290nm, both inclusive. When the non-magnetic layer is made of tantalum, thefirst non-magnetic layer may preferably have a thickness between 1.5 nmand 10 nm, both inclusive and the second non-magnetic layer maypreferably have a thickness between 8 nm and 290 nm, both inclusive.When the non-magnetic layer is made of chromium, the first non-magneticlayer may preferably have a thickness between 2.5 nm and 10 nm, bothinclusive and the second non-magnetic layer may preferably have athickness between 12 nm and 290 nm, both inclusive. This reason will belater described. In other words, the non-magnetic layer may desirablycomprise a lamina made of metal having a tensile stress.

[0032] Preferably, the magnetic layer may comprise a single-layerstructure of essential elements of cobalt (Co), nickel (Ni), and iron(Fe) or may comprise a laminated structure of a first magnetic sub-layerof essential elements of cobalt (Co), nickel (Ni), and iron (Fe) and asecond magnetic sub-layer of essential elements of nickel (Ni) and iron(Fe). When the magnetic layer comprises the laminated structure, thefirst magnetic sub-layer is disposed near to the recording gap layer.The magnetic layer (first magnetic sub-layer) of the essential elementsof cobalt (Co), nickel (Ni), and iron (Fe) may preferably have a crystalstructure selected from the group consisting of a face-centered cubic(fcc) structure, a body-centered cubic (bcc) structure, and a mixedcrystal with a face-centered cubic (fcc) structure and a body-centeredcubic (bcc) structure and may preferably have a crystal particlediameter which is not more than 20 nm. This is because such a magneticlayer becomes a high-Bs soft magnetic film.

[0033] In addition, the magnetic layer may desirably comprise a laminaselected from the group consisting essentially of cobalt-iron-nickel(CoFeNi), cobalt-iron-copper (CoFeCu), cobalt-iron-molybdenum (CoFeMo),cobalt-iron-boron (CoFe), and cobalt-iron (CoFe). The lamina maycomprise alloy or mixture. The lamina may comprise one selected from asingle-layer film and a multi-layer film. The mixture further maycomprise an additional alloy consisting essentially of nickel-iron(NiFe).

[0034] A combination of the insulating layer and the write coil may bemade by successively laminating a first insulating layer, the writecoil, and a second insulating layer, a periphery end of the secondinsulating layer on a side of an air bearing surface (ABS) may be closeto the air bearing surface than a periphery end of the first insulatinglayer. In this event, inasmuch as a periphery of the second insulatinglayer is outside a periphery of the first insulating layer, a boundaryface between the second insulating layer and the first insulating layeris not exposed to the outside. Accordingly, inasmuch as the stress ofthe second magnetic layer is applied to the boundary face between thesecond insulating layer and the first insulating layer, crack does notoccur in the boundary face in question.

BRIEF DESCRIPTION OF THE DRAWING

[0035]FIG. 1 is an air bearing surface (ABS) view of a conventionalmagnetic head;

[0036]FIG. 2 is a vertical sectional view taken along the lines II-II ofFIG. 1;

[0037]FIG. 3 is an air bearing surface (ABS) view of a magnetic headaccording to a first embodiment of this invention;

[0038]FIG. 4 is a vertical sectional view taken along the lines IV-IV ofFIG. 3;

[0039]FIG. 5 is a perspective view of a magnetic head according to thisinvention;

[0040]FIG. 6 is a block diagram showing the magnetic storage unit onwhich the magnetic head illustrated in FIG. 5 is mounted;

[0041]FIG. 7 is an air bearing surface (ABS) view of a magnetic headaccording to a second embodiment of this invention:

[0042]FIG. 8 is a vertical sectional view taken along the linesVIII-VIII of Fig;

[0043]FIG. 9 is an air bearing surface (ABS) view of a magnetic headaccording to a third embodiment of this invention; and

[0044]FIG. 10 is a vertical sectional view taken along the lines X-X ofFIG. 9.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0045] Referring to FIGS. 1 and 2, a conventional magnetic head willfirst be described in order to facilitate an understanding of thepresent invention. FIG. 1 is an air bearing surface (ABS) view of theconventional magnetic head. FIG. 2 is a vertical sectional view takenalong the lines II-II of FIG. 1.

[0046] In the manner which will later become clear, the illustratedmagnetic head is a merged GMR head which comprises a giantmagnetoresistence (GMR) read head and an inductive (ID) write head.Description will be first directed to the GMR read head and will besubsequently directed to the ID write head.

[0047] The magnetic head comprises a substrate 10 having a principalsurface 10 a. The substrate 10 comprises a ceramic substrate 11 (whichis omitted in FIG. 1) serving as a slider, a first or lower magneticshield layer 12 formed on the ceramic substrate 11, a magneticseparation layer 13 formed on the first magnetic shield layer 12, and aGMR element 14 sandwiched in the magnetic separation layer 13. Inaddition, formed on the magnetic separation layer 13, a second magneticshield layer 15 doubles as a first or lower magnetic layer 16 of the IRwrite head. A combination of the first magnetic shield layer 12, themagnetic separation layer 13, the GMR element 14, and the secondmagnetic shield layer 15 serves as the GMR read head.

[0048] As shown in FIG. 1, the GMR element 14 comprises a center area141 and end areas 142 which are disposed in both ends of the center area141. The center area 141 is made of a spin valve laminated structure forgenerating a GMR effect. The end areas 142 is for supplying an electriccurrent and a bias magnetic field.

[0049] On the other hand, the ID read head comprises the first or lowermagnetic layer 16 formed on the principal surface 10 a of the substrate10, a recording gap layer 17, a first insulating layer 18 formed on therecording gap layer 17 except for a pole tip region, a write coil 19formed on the first insulating layer 18, a second insulating layer 20formed on the first insulating layer 18 so as to cover the write coil19, and a second or upper magnetic layer 21 formed on the pole chipregion of the recording gap layer 17 and on the first and the secondinsulating layers 18 and 20. That is, the write coil 19 is enclosed withand insulated by a combination of the first and the second insulatinglayers 18 and 20. With this structure, information is recorded on amagnetic recording medium (not shown) by a magnetic flux which leaks inthe magnetic gap layer 17 between the first and the second magneticlayers 16 and 21 magnetized by a magnetic field generated by the writecoil 19.

[0050] A boundary face 181 between the first and the second insulatinglayers 18 and 20 is called a step cover (SC) film.

[0051] Each of the first and the second magnetic layers 19 and 21 may bemade of a high-Bs soft magnetic film which is disclosed in theabove-mentioned JP-B 2821456. However, following problems occur, asmentioned in the preamble of the instant specification. That is,stripping occurs in the first and the second magnetic layers 16 and 21.In addition, cracks occur in the step cover (SC) film or the boundaryface 181 between the first and the second insulating layers 18 and 20.Furthermore, cracks occur in a frame resist on forming the high-Bs softmagnetic film, the plating film grows along the cracks, and thenabnormality in shape occurs in the first and the second magnetic layers16 and 21.

[0052] Referring to FIGS. 3 and 4, the description will proceed to amagnetic head according to a first embodiment of this invention. FIG. 3is an air bearing surface (ABS) view of the magnetic head. FIG. 4 is avertical sectional view taken along the lines IV-IV of FIG. 3. In FIGS.3 and 4, similar components and part to those in FIGS. 1 and 2 aredepicted by like reference numerals and description of such componentsand parts will be omitted.

[0053] The illustrated magnetic head is a merged G head which comprisesa giant magnetoresistence (GMR) read head and an inductive (ID) writehead.

[0054] The magnetic head comprises the ceramic substrate 11 serving asthe slider. The ceramic substrate 11 is made of complex or compositeceramic consisting of alumina (Al₂O₃) and titanium carbide. On theceramic substrate 11, the GMR read head having a reproducing function isformed.

[0055] The GRM read head comprises the first magnetic shield layer 12,the second magnetic shield layer 15, the magnetic separation layer 13,and the GMR element 14. Formed on the ceramic substrate, the firstmagnetic shield layer 12 is made of a patternedcobalt-zirconium-tantalum (CoZrTa) film The second magnetic shieldinglayer 15 is made of a nickel-iron (NiFe) film which contains about 80%by weight of nickel (Ni). Disposed between the first and the secondmagnetic shield layers 12 and 15, the magnetic separation layer 13 ismade of alumina (Al₂O₃). The first magnetic shield layer 12 has athickness of 1 μm and the second magnetic shield layer 15 has athickness of 3 μm. In addition, a gap of the first magnetic shield layer12 and the second magnetic shield layer 15 is equal to 0.13 μm.

[0056] As shown in FIG. 3, the GMR element 14 comprises the center area141 and the end areas 142 which are disposed in both ends of the centerarea 141. The center area 141 is for sensing a magnetic field from amagnetic recording medium (not shown) while the end areas 142 is forsupplying the center area 141 with an electric current and a biasmagnetic field. The center area 141 is made of a laminated structurehaving a GMR effect which is generally called a spin valve effect.Specifically, formed on the first magnetic shield layer 12, the centerarea 141 comprises the laminated structure consisting of an undercoatingzirconium (Zr) film having a thickness of about 3 nm, aplatinum-manganese (PtMn) film having a thickness of about 20 nm, acobalt-iron (CoFe) film having a thickness of about 2 nm, a copper (Cu)film having a thickness of about 2.1 nm, a cobalt-iron (CoFe) filmhaving a thickness of about 0.5 nm, a nickel-iron (NiFe) film having athickness of about 2 nm, and a zirconium (Zr) film having a thickness ofabout 3 nm in this order. The center area 141 has a width of 0.5 μmwhich defines a reproducing track width. Each end area 142 has alaminated structure which comprises a permanent magnet film and anelectrode film. The permanent magnet film is, for example, acobalt-platinum (CoPt) film having a thickness of about 20 nm. Theelectrode film is, for example, a gold (Au) film having a thickness ofabout 50 nm.

[0057] On the GMR read head, the ID write head is formed. Specifically,on the magnetic separation layer 13, the first magnetic layer 16 isformed through a first non-magnetic layer 22 and a first conductivelayer 23. The first magnetic layer 16 doubles the second magnetic shieldlayer 15. The first non-magnetic layer 22 is made of titanium (Ti) andhas a thickness of about 3 nm. The first conductive layer 23 is made ofnickel-iron (NiFe) and has a thickness of about 100 nm. The firstmagnetic layer 16 has a laminated structure which comprises anickel-iron (NiFe) film having a thickness of about 2.0 μm and acobalt-nickel-iron (CoNiFe) film having a thickness of about 0.5 μm andincluding no stress relieving agent such as saccharin.

[0058] Inasmuch as the first magnetic layer 16 is formed on the magneticseparation layer 13 through the first non-magnetic layer 22, it ispossible to improve adhesion between the first magnetic layer 16 and themagnetic separation layer 13. Accordingly, it is possible to prevent thefirst magnetic layer 16 from stripping caused by a stress in thecobalt-nickel-iron (CoNiFe) film which is a component of the firstmagnetic layer 16. Although adhesion is good when a thickness of thefirst nonmagnetic layer 22 is 2 nm or more, the thickness of the firstnon-magnetic layer 22 is limited to an upper limit of 10 nm because thereproducing gap length widens too if the thickness of the firstnon-magnetic layer 22 is move than 10 nm. At any rate, a combination ofthe first non-magnetic layer 22 and the first conductive layer 23 servesas a first antistripping layer for preventing the first magnetic layer16 from stripping.

[0059] The ID write head comprises the second magnetic shield layer 15as the first magnetic layer 16, the recording gap layer 17 formed on thefirst magnetic layer 16, and the first insulating layer 18 formed on therecording gap layer 17 except for a pole tip region. The firstinsulating layer 18 defines a zero throat height which is well known inthe art. The recording gap layer 17 has a thickness of about 0.15 μm andis made of alumina (Al₂O₃), The first insulating layer 18 consists of aphoto-resist. In addition, on the first insulating layer 18 is formedthe write coil 19 which consists of a copper (Cu) plating film.Furthermore, the second insulating layer 20 is formed on the firstinsulating layer 18, the write coil 19, and the recording gap layerexcept for an pole tip region so as to cover a peripheral part of thefirst insulating layer 18. The write coil 19 is insulated by the secondinsulating layer 20. The second insulating layer 20 consist of aphoto-resist. With this structure, a boundary face 181 between the firstinsulating layer 18 and the second insulating layer 20 is not exposed tothe side of the second magnetic layer 21. Accordingly, it is possible toprevent the boundary face 181 from cracking caused by a stress of thecobalt-nickel-iron (CoNiFe) film which includes no stress relievingagent such as saccharin and which is a component of the second magneticlayer 21.

[0060] On the pole tip region of the recording gap layer 17 and thesecond insulating layer 20, the second magnetic layer 21 is formedthrough a second non-magnetic layer 24 and a second conductive layer 25.The second non-magnetic layer 24 is made of titanium (Ti) and has athickness of about 50 nm. The second conductive layer 25 is made ofnickel-iron (NiFe) and has a thickness of about 50 nm. The secondmagnetic layer 21 comprises a laminated film which consists of thecobalt-nickel-iron (CoNiFe) film having a thickness of about 0.5 μm anda nickel-iron (NiFe) film having a thickness of about 2.8 μm. The secondmagnetic layer 21 exposes to an air bearing surface (ABS) which faces ona magnetic recording medium (not shown).

[0061] Inasmuch as the second magnetic layer 21 is formed on the secondinsulating layer 20 through the second non-magnetic layer 24, adhesionbetween the second magnetic layer 21 and the recording gap layer 17 andbetween the second magnetic layer 21 and the second insulating layer 20improves and a stress of the cobalt-nickel-iron (CoNiFe) film in thesecond magnetic layer 21 decreases. Accordingly, it is possible toprevent the second magnetic layer 21 from stripping caused by the stressof the cobalt-nickel-iron (CoNiFe) which includes no stress relievingagent such as saccharin and which is a component of the second magneticlayer 21. At any rate, a combination of the second non-magnetic layer 24and the second conductive layer 25 serves as a second antistrippinglayer for preventing the second magnetic layer 21 from stripping.

[0062] A thickness of 10 nm or more is required for the secondnon-magnetic layer 24 to obtain adhesion between the second insulatinglayer 20 and the second magnetic layer 21 and to decrease the stress ofthe cobalt-nickel-iron (CoNiFe) film in the second magnetic layer 21.

[0063] The second non-magnetic layer 24 acts as a part of an effectiverecording gap. It is assumed that the effective recording gap has alength of a, the recording gap layer 17 has a thickness of b, and thesecond non-magnetic layer 24 has a thickness of c. In this event, thelength a of the effective recording gap is equal to a sum of thethickness b of the recording gap layer 17 and the thickness c of thesecond Ad non-magnetic layer 24, namely, a=(b+c). In addition, it isdesirable that the length a of the effective recording gap lies a rangebetween 50 nm and 300 nm, both inclusive. Accordingly, the sum (b+c)lies a range between 50 nm and 300 nm, both inclusive. On the otherhand, the thickness b of 10 nm or more is required for the recording gaplayer 17 to electrically separate the first magnetic layer 16 from thesecond magnetic layer 21 at the air bearing surface (ABS). Accordingly,to satisfy there conditions, the thickness c of the second non-magneticlayer 24 has an upper limit value of 290 nm.

[0064] Referring to FIGS. 5 and 6, the description will proceed to amagnetic head according to this invention and a magnetic storage unit onwhich the magnetic head illustrated in FIG. 5 is mounted. FIG. 5 is aperspective view of the magnetic head according to this invention. FIG.6 is a block diagram showing the magnetic storage unit on which themagnetic head illustrated in FIG. 5 is mounted.

[0065] As shown in FIG. 5, the magnetic head 30 comprises a slider 31,electrodes 32, and a recording and reproducing element 33. The slider 31corresponds to the ceramic substrate 11 illustrated in FIGS. 3 and 4.The recording and reproducing element 33 corresponds to a combination ofthe first magnetic shielding layer 12, the magnetic separation layer 13,the GMR element 14, the second magnetic shielding layer 15 (or the firstmagnetic layer 16, the recording gap layer 17, the first insulatinglayer 18, the write coil 19, the second insulating layer 20, the secondmagnetic layer 21, the first non-magnetic layer 22, the first conductivelayer 23, the second non-magnetic layer 24, and the second conductivelayer 25 illustrated in FIGS. 3 and 4.

[0066] As shown in FIG. 6, the magnetic storage unit 40 comprises themagnetic head 30 illustrated FIG. 5, a magnetic recording medium 41having a magnetic recording surface, and a spindle motor 32 forrotatably driving the magnetic recording medium 41. The magnetic head 30is mounted by a suspension member 43 and an arm 44 to face to themagnetic recording surface of the magnetic recording medium 41. Themagnetic head 30 is tracked on the magnetic recording medium 41 by avoice coil motor (VCM) 45. That is, the voice coil motor 45 carries outpositioning of the magnetic head 30. In the magnetic storage unit 40,magnetic recording and reproducing operation is carried out by a signalwhich is supplied from a recording and reproducing channel 46 to themagnetic head 30. The recording and reproducing channel 46, the voicecoil motor 45, and the spindle motor 32 are controlled by a control unit47.

[0067] With this structure, it is possible to realize the magneticstorage unit 40 having a recording density of about 10 gigabits/inch² ormore when the magnetic recording medium 41 has a coercive forceof278600A/m and when a magnetic distance between the magnetic recordingmedium 41 and the magnetic head 30 is equal to about 35 nm.

[0068] Referring to FIGS. 7 and 8, the description will proceed to amagnetic head according to a second embodiment of this invention. FIG. 7is an air bearing surface (ABS) view of the magnetic head. FIG. 8 is avertical sectional view taken along the lines VIII-VIII of FIG. 7. InFIGS. 7 and 8, similar components and part to those in FIGS. 3 and 4 aredepicted by like reference numerals and description of such componentsand parts will be omitted.

[0069] The illustrated magnetic head is similar in structure andoperation to the magnetic head illustrated in FIGS. 3 and 4 except thatthe second non-magnetic layer 24 and the second conductive layer 25 areomitted from the magnetic head illustrated in FIGS. 3 and 4. In otherwords, the illustrated magnetic head is provided with the firstnon-magnetic layer 22 and the first conductive layer 23 alone. With thisstructure, it is possible to prevent the first magnetic layer 16 fromstripping caused by a stress in the CoNiFe film which includes no stressrelieving agent such as saccharin and which is a component of the firstmagnetic layer 16.

[0070] Referring to FIGS. 9 and 10, the description will proceed to amagnetic head according to a third embodiment of this invention. FIG. 9is an air bearing surface (ABS) view of the magnetic head. FIG. 10 is avertical sectional view taken along the lines X-X of FIG. 9. In FIGS. 9and 10, similar components and part to those in FIGS. 3 and 4 aredepicted by like reference numerals and description of such componentsand parts will be omitted.

[0071] The illustrated magnetic head is similar in structure andoperation to the magnetic head illustrated in FIGS. 3 and 4 except thatthe first non-magnetic layer 22 and the first conductive layer 23 areomitted from the magnetic head illustrated in FIGS. 3 and 4. In otherwords, the illustrated magnetic head is provided with the secondnon-magnetic layer 24 and the second conductive layer 25 alone. Withthis structure, it is possible to prevent the second magnetic layer 21from stripping caused by the stress of the CoNiFe which includes nostress relieving agent such as saccharin and which is a component of thesecond magnetic layer 21.

[0072] Now, description will proceed to actual examples of the magnetichead according to this invention. It is noted throughout thespecification hereunder that composition of material is represented onthe basis of an atomic percent (at %) and a value put in parenthesesrepresents a thickness of a layer, a film, or a lamina.

[0073] Firstly, a wrong occurrence resist effect by the firstnon-magnetic layer 22 is examined in a case of using a two-layer film ofnickel-iron (NiFe)/cobalt-iron-nickel (CoFeNi) as the first magneticlayer 16.

[0074] Tables 1, 2, and 3 show probability of occurrence of stripping inthe first magnetic layer 16, probability of occurrence of crack in thesecond insulating layer 20, and probability of occurrence of shapeanomaly in the first magnetic layer 16 in a case of manufacturing themagnetic head having structure illustrated in FIGS. 3 and 4 by using alamina made of metal selected from titanium (Ti), tantalum (Ta), andchromium (Cr) as the first nonmagnetic layer 22 and by changingthickness thereof. In elements used in measurement, the first magneticlayer 16 doubling as the second magnetic shield layer 15 comprises thetwo-layer film (which laminates CoFeNi on NiFe) made of Ni₈₀Fe₂₀ (1.0μm)/Co₆₅Fe₂₃Ni₁₂ (1.0 μm) formed by plating with using no stressrelaxation agent and the second magnetic layer 21 comprises asingle-layer film made of Co₆₅Fe₂₃Ni₁₂ (1.4 μm) formed by plating withusing no stress relaxation agent. The second non-magnetic layer 24 ismade of titanium (Ti) and has a thickness of 30 nm. As result, wrongsuch as stripping caused by the second magnetic layer 21, occurrence ofcrack, and shape anomaly are not occurred. On manufacturing, followingis used as each element of the magnetic head. Composition of eachmaterial described below is composition (at %) of a target for use insputtering.

[0075] The ceramic substrate 11 comprises a substrate made of aluminatitanium carbide (Al₂O₃—TiC) having a thickness of 1.2 mm on whichalumina (Al₂O₃) is laminated by 3 μm. The first magnetic shield layer 12is made of Co₈₉Zr₄Ta₄Cr₃ (1 μm). A vertical bias grounding layer is madeof chromium (Cr) (10 nm). A vertical bias is made ofCo_(74.5)Cr_(10.5)Pt₁₅ (16 nm). The magnetic separation layer 15 is madeof alumina (Al₂O₃). The GMR element 15 has a laminated structureconsisting of tantalum (Ta) (3 nm), Pt₄₆Mn₅₄ (20 nm), Co₉₀Fe₁₀ (3 nm),ruthenium (Ru) (0.7 nm), Co₉₀Fe₁₀ (3 nm), copper (Cu) (2.1 nm), Co₉₀Fe₁₀(0.5 nm), Ni₈₂Fe₁₈ (1 nm), copper (Cu) (2 nm) , and tantalum (Ta) (3nm). The first conductive layer 23 is made of Ni₈₀Fe₂₀ (100 nm). Therecording gap layer 17 is made of alumina (Al₂O₃) (0.18 μm). The writecoil 19 is made of copper (Cu) (1.8 μm). The second conductive layer 25is made of Ni₈₀Fe₂₀ (50 nm). The second insulating layer 20 comprises aresist. TABLE 1 PROBABILITY OF OCCURRENCE PROBABILITY OF OCCURRENCEPROBABLITY OF OCCURRENCE THICKNESS OF Ti OF STRIPPING IN OF CRACK IN 2NDOF SHAPE ANOMALY IN LAYER (nm) 1ST MAGNETIC LAYER (%) INSULATING LAYER(%) 1ST MAGNETIC LAYER (%) 0 82 72 66 0.5 85 74 68 1.0 72 63 55 1.5 5041 36 2.0 9 2 0 2.5 6 0 0 3.0 3 0 0 4.0 0 0 0 5.0 0 0 0 7.0 0 0 0 10.0 00 0 20.0 0 0 0

[0076] TABLE 2 PROBABILITY OF OCCURRENCE PROBABILITY OF OCCURRENCEPROBABLITY OF OCCURRENCE THICKNESS OF Ta OF STRIPPING IN OF CRACK IN 2NDOF SHAPE ANOMALY IN LAYER (nm) 1ST MAGNETIC LAYER (%) INSULATING LAYER(%) 1ST MAGNETIC LAYER (%) 0 82 72 66 0.5 80 72 60 1.0 62 59 47 1.5 1411 7 2.0 5 3 2 2.5 2 2 0 3.0 0 0 0 4.0 0 0 0 5.0 0 0 0 7.0 0 0 0 10.0 00 0 20.0 0 0 0

[0077] TABLE 3 PROBABILITY OF OCCURRENCE PROBABILITY OF OCCURRENCEPROBABLITY OF OCCURRENCE THICKNESS OF Cr OF STRIPPING IN OF CRACK IN 2NDOF SHAPE ANOMALY IN LAYER (nm) 1ST MAGNETIC LAYER (%) INSULATING LAYER(%) 1ST MAGNETIC LAYER (%) 0 82 72 66 0.5 79 71 61 1.0 72 64 59 1.5 6458 49 2.0 59 53 46 2.5 12 9 7 3.0 7 4 3 4.0 4 1 1 5.0 0 0 0 7.0 0 0 010.0 0 0 0 20.0 0 0 0

[0078] In a case of using a titanium (Ti) layer as the firstnon-magnetic layer 22, stripping caused by the first magnetic layer 16,occurrence of crack, and shape anomaly occur at a large probability of30% or more when the titanium (Ti) layer has a thickness of 1.5 nm orless. When the titanium (Ti) layer has a thickness of 2.0 nm or more,the probability of occurrence of respective wrongs is lowered to several% or less and the wrong occurrence resist effect caused by the firstnon-magnetic layer 22 made of titanium (Ti) presents.

[0079] In a case of using a tantalum (Ta) layer as the firstnon-magnetic layer 22, stripping caused by the first magnetic layer 16,occurrence of crack, and shape anomaly occur at a large probability of40% or more when the tantalum (Ta) layer has a thickness of 1.0 nm orless. When the tantalum (Ta) layer has a thickness of 1.5 nm or more,the probability of occurrence of respective wrongs is lowered to someten % or less and the wrong occurrence resist effect caused by the firstnon-magnetic layer 22 made of tantalum (Ta) presents.

[0080] In a case of using a chromium (Cr) layer as the firstnon-magnetic layer 22, stripping caused by the first magnetic layer 16,occurrence of crack, and shape anomaly occur at a large probability of40% or more when the chromium (Cr) layer has a thickness of 2.0 nm orless. When the Ca layer has a thickness of 2.5 nm or more, theprobability of occurrence of respective wrongs is lowered to some ten %or less and the wrong occurrence resist effect caused by the firstnon-magnetic layer 22 made of chromium (Cr) presents.

[0081] Secondary, incidence of wrong is measured by using a single-layerfilm of an alloy made of cobalt-iron-nickel (CoFeNi) as the firstmagnetic layer 16 and by manufacturing the magnetic head withcomposition of the alloy made of cobalt-iron-nickel (CoFeNi) changed.

[0082] Table 4 shows thickness of the first non-magnetic layer 22 madeof titanium (Ti) having the thinnest thickness where each of theprobability of occurrence of stripping in the first magnetic layer 16,the probability of occurrence of crack in the second insulating layer20, and the probability of occurrence of shape anomaly in the firstmagnetic layer 16 in a case of using a titanium (Ti) layer as the firstnon-magnetic layer 22. In this event, the first magnetic layer 16doubling as the second magnetic shield layer 15 comprises one of threetypes of the single-layer film made of cobalt-iron-nickel (CoFeNi)having different composition (Co₆₅Fe₂₃Ni₁₂, Co₄₃Fe₁₆Ni₄₁, Co₈₀Fe₉Ni₁₁)having a thickness of 2 μm each of which formed by plating with using nostress relaxation agent. In elements used measurement, the secondmagnetic layer 21 comprises a single-layer film made of Co₆₅Fe₂₃Ni₁₂(1.4 μm) formed by plating with using no stress relaxation agent Thesecond non-magnetic layer 24 is made of titanium (Ti) having a thicknessof 30 nm in order to resist occurrence of wrong caused by the secondmagnetic layer 24. As result, wrong such as stripping caused by thesecond magnetic layer 21, occurrence of crack, and shape anomaly is notoccurred. As each element of the magnetic head, similar ones used inthose to obtain data in Tables 1 to 3 are used. TABLE 4 MINIMUMTHICKNESS OF MINIMUM THICKNESS OF MINIUM THICKNESS OF Ti LAYER WHERE TiLAYER WHERE Ti LAYER WHERE PROBABILITY OF OCCURRENCE PROBABILITY OFOCCURRENCE PROBABILITY OF OCCURRENCE OF STRIPPING IN 1ST OF CRACK IN 2NTOF SHAPE ANOMALY IN COMPOSITION OF 1ST MAGNETIC LAYER IS INSULATINGLAYER IS 1ST MAGNETIC LAYER IS MAGNETIC LAYER (at %) LESS THAN 20% (nm)LESS THAN 20% (nm) LESS THAN 20% (nm) Co₆₆Fe₂₃Ni₁₂ 2.0 2.0 2.0Co₄₃Fe₁₅Ni₄₁ 2.0 2.0 2.0 Co₈₀Fe₉Ni₁₁ 2.0 2.0 2.0

[0083] The thickness of the first non-magnetic layer 22 made of titanium(Ti) having the thinnest thickness where each of the probability ofoccurrence of stripping in the first magnetic layer 16, the probabilityof occurrence of crack in the second insulating layer 20, and theprobability of occurrence of shape anomaly in the first magnetic layer16 is less than 20% is 2.0 nm in the case of any composition. Differenceis not present in the wrong occurrence resist effect caused by the firstnon-magnetic layer 22 made of titanium (Ti) although the composition ofthe alloy made of cobalt-iron-nickel (CoFeNi) differs from each other.

[0084] Thirdly, a wrong occurrence resist effect caused by the secondnon-magnetic layer 24 is examined in a case of using a two-layer filmmade of cobalt-iron-nickel (CoFeNi)/nickel-iron (NiFe) as the secondmagnetic layer 21.

[0085] Tables 5, 6, and 7 show probability of occurrence of stripping inthe second magnetic layer 21, probability of occurrence of crack in thesecond insulating layer 20, and probability of occurrence of shapeanomaly in the second magnetic layer 21 in a case of manufacturing themagnetic head having structure illustrated in FIGS. 3 and 4 by using alamina made of metal selected from titanium (Ti), tantalum (Ta), andchromium (Cr) as the second non-magnetic layer 24 and by changingthickness thereof. In elements used in measurement, the first magneticlayer 16 doubling as the second magnetic shield layer 15 comprises asingle-layer film made of Co65Fe₂₃Ni₁₂ (2.0 μm) formed by plating withusing no stress relaxation agent and the second magnetic layer 21comprises a two-layer film made of Co₆₅Fe₂₃Ni₁₂ (0.7 μm)/Ni₈₀Fe₂₀ (0.7μm) formed by plating with using no stress relaxation agent. The firstnon-magnetic layer 22 is made of titanium (Ti) having a thickness of 5nm. As result, wrong such as stripping caused by the first magneticlayer 16, occurrence of crack, and shape anomaly is not occurred. Onmanufacturing, as each element of the magnetic head, similar ones usedin those to obtain data in Tables 1 to 3 are used. TABLE 5 PROBABILITYOF OCCURRENCE PROBABILITY OF OCCURRENCE PROBABILITY OF OCCURRENCETHICKNESS OF Ti OF STRIPPING IN OF CRACK IN 2ND OF SHAPE ANOMALY INLAYER (nm) 2ND MAGNETIC LAYER (%) INSULATING LAYER (%) 2ND MAGNETICLAYER (%) 0 95 87 77 5.0 92 84 79 8.0 77 71 65 9.0 62 57 51 10.0 13 9 612.0 7 4 3 15.0 0 0 0 20.0 0 0 0 40.0 1 0 0 100.0 0 0 0

[0086] TABLE 6 PROBABILITY OF OCCURRENCE PROBABILITY OF OCCURRENCEPROBABILITY OF OCCURRENCE THICKNESS OF Ta OF STRIPPING IN OF CRACK IN2ND OF SHAPE ANOMALY IN LAYER (nm) 2ND MAGNETIC LAYER (%) INSULATINGLAYER (%) 2ND MAGNETIC LAYER (%) 0 95 87 77 7.0 72 64 59 8.0 19 11 9 9.07 4 1 10.0 3 2 1 12.0 1 0 0 15.0 0 0 0 20.0 0 0 0 40.0 1 1 1 100.0 0 0 0

[0087] TABLE 7 PROBABILITY OF OCCURRENCE PROBABILITY OF OCCURRENCEPROBABILITY OF OCCURRENCE THICKNESS OF Cr OF STRIPPING IN OF CRACK IN2ND OF SHAPE ANOMALY IN LAYER (nm) 2ND MAGNETIC LAYER (%) INSULATINGLAYER (%) 2ND MAGNETIC LAYER (%) 0 95 87 77 5.0 91 82 75 8.0 77 69 679.0 67 54 49 10.0 52 43 36 12.0 17 12 9 15.0 3 2 1 20.0 1 1 0 40.0 2 1 1100.0 1 0 0

[0088] In a case of using a titanium (Ti) layer as the secondnon-magnetic layer 24, stripping caused by the second magnetic layer 21,occurrence of crack, and shape anomaly occur at a large probability of50% or more when the titanium (Ti) layer has a thickness of 9.0 nm orless. When the titanium (Ti) layer has a thickness of 10.0 nm or more,the probability of occurrence of respective wrongs is lowered to someten % or less and the wrong occurrence resist effect caused by thesecond non-magnetic layer 24 made of titanium (Ti) presents.

[0089] In a case of using a tantalum (Ta) layer as the secondnon-magnetic layer 24, stripping caused by the second magnetic layer 21,occurrence of crack, and shape anomaly occur at a large probability of50% or more when the tantalum (Ta) layer has a thickness of 7.0 nm orless. When the tantalum (Ta) layer has a thickness of 8.0 nm or more,the probability of occurrence of respective wrongs is lowered to someten % or less and the wrong occurrence resist effect caused by thesecond non-magnetic layer 24 made of tantalum (Ta) presents.

[0090] In a case of using a chromium (Cr) layer as the secondnon-magnetic layer 24, stripping caused by the second magnetic layer 21,occurrence of crack, and shape anomaly occur at a large probability of30% or more when the chromium (Cr) layer has a thickness of 10.0 nm orless. When the chromium (Cr) layer has a thickness of 12.0 nm or more,the probability of occurrence of respective wrongs is lowered to someten % or less and the wrong occurrence resist effect caused by thesecond non-magnetic layer 24 made of chromium (Cr) presents.

[0091] Fourthly, incidence of wrong is measured by using a single-layerfilm of an alloy made of cobalt-iron-nickel (CoFeNi) as the secondmagnetic layer 21 and by manufacturing the magnetic head withcomposition of the alloy made of cobalt-iron-nickel (CoFeNi) changed.

[0092] Table 8 shows thickness of the second non-magnetic layer 24 madeof titanium (Ti) having the thinnest thickness where each of theprobability of occurrence of stripping in the second magnetic layer 21,the probability of occurrence of crack in the second insulating layer20, and the probability of occurrence of shape anomaly in the secondmagnetic layer 21 in a case of using a titanium (Ti) layer as the secondnon-magnetic layer 24. In this event, the second magnetic layer 16comprises one of three types of the single-layer film made ofcobalt-iron-nickel (CoFeNi) having different composition (Co₆₅Fe₂₃Ni₁₂,Co₄₃Fe₁₆Ni₄₁, Co₈₀Fe₉Ni₁₁) having a thickness of 1.2 μm each of whichformed by plating with using no stress relaxation agent. In elementsused measurement, the first magnetic layer 16 doubling as the secondmagnetic shield layer 15 comprises a single-layer film made ofCo₆₅Fe₂₃Ni₁₂ (2.0 μm) formed by plating with using no stress relaxationagent. The first non-magnetic layer 22 is made of titanium (Ti) having athickness of 5 nm. As result, wrong such as stripping caused by thefirst magnetic layer 16, occurrence of crack, and shape anomaly is notoccurred. As each element of the magnetic head, similar ones used inthose to obtain data in Tables 1 to 3 are used. TABLE 8 MINIMUMTHICKNESS OF MINIMUM THICKNESS OF MINIUM THICKNESS OF Ti LAYER WHERE TiLAYER WHERE Ti LAYER WHERE PROBABILITY OF OCCURRENCE PROBABILITY OFOCCURRENCE PROBABILITY OF OCCURRENCE OF STRIPPING IN 2ND OF CRACK IN 2NDOF SHAPE ANOMALY IN COMPOSITION OF 2ND MAGNETIC LAYER IS INSULATINGLAYER IS 2ND MAGNETIC LAYER IS MAGNETIC LAYER (at %) LESS THAN 20% (nm)LESS THAN 20% (nm) LESS THAN 20% (nm) Co₆₅Fe₂₃Ni₁₂ 10.0 10.0 10.0Co₄₃Fe₁₅Ni₄₁ 10.0 10.0 10.0 Co₈₀Fe₉Ni₁₁ 10.0 10.0 10.0

[0093] The thickness of the second nonmagnetic layer 24 made of titanium(Ti) having the thinnest thickness where each of the probability ofoccurrence of stripping in the second magnetic layer 21, the probabilityof occurrence of crack in the second insulating layer 20, and theprobability of occurrence of shape anomaly in the second magnetic layer21 is less than 20% is 10.0 nm in the case of any composition.Difference is not present in the wrong occurrence resist effect causedby the second non-magnetic layer 24 made of titanium (Ti) although thecomposition of the alloy made of cobalt-iron-nickel (CoFeNi) differsfrom each other.

[0094] Fifthly, examination is made in a case of using, as the first andthe second magnetic layers 16 and 21, materials except for the two-layerfilm made of cobalt-iron-nickel (CoFeNi) and nickel-iron (NiFe) and thesingle-layer film made of cobalt-iron-nickel (CoFeNi).

[0095] Tables 9, 10, 11, and 12 show probability of occurrence ofstripping in the first magnetic layer 16, probability of occurrence ofcrack in the second insulating layer 20, and probability of occurrenceof shape anomaly in the first magnetic layer 16 in a case ofmanufacturing the magnetic head having structure illustrated in FIGS. 3and 4 by using, as the first non-magnetic layer 22, a lamina made ofmetal selected from titanium (Ti), tantalum (Ta), and chromium (Cr) eachhaving a thickness of 5 nm and by using, as the first magnetic layer 16doubling as the second magnetic shield layer 15, a single-layer filmmade of one selected from Co₇₄Fe₂₃Cu₃, Co₇₂Fe₂₄Mo₄, and Co₇₇Fe₁₉B₄, andCo₉₀Fe₁₀ formed by plating with using no stress relaxation agent,respectively. In elements used in measurement, the second magnetic layer21 comprises a single-layer film made of Co₆₅Fe₂₃Ni₁₂ (1.4 μm) formed byplating with using no stress relaxation agent. In order to resist wrongoccurrence caused by the second magnetic layer 21, the secondnon-magnetic layer 24 is made of titanium (Ti) having a thickness of 30nm. As result, wrong such as stripping caused by the second magneticlayer 21, occurrence of crack, and shape anomaly is not occurred. Aseach element of the magnetic head, similar ones used in those to obtaindata in Tables 1 to 3 are used. TABLE 9 A case of the first magneticlayer 16 made of Co₇₄Fe₂₃Cu₃ PROBABILITY OF OCCURRENCE PROBABILITY OFOCCURRENCE PROBABILITY OF OCCURRENCE KIND OF 1ST NON- OF STRIPPING IN OFCRACK IN 2ND OF SHAPE ANOMALY IN MAGNETIC LAYER 1ST MAGNETIC LAYER (%)INSULATING LAYER (%) 1ST MAGNETIC LAYER (%) NONE 72 62 56 Ti (5 nm) 3 22 Ta (5 nm) 0 0 0 Cr (5 nm) 7 4 3

[0096] TABLE 10 A case of the first magnetic layer 16 made ofCo₇₂Fe₂₄Mo₄ PROBABILITY OF OCCURRENCE PROBABILITY OF OCCURRENCEPROBABILITY OF OCCURRENCE KIND OF 1ST NON- OF STRIPPING IN OF CRACK IN2ND OF SHAPE ANOMALY IN MAGNETIC LAYER 1ST MAGNETIC LAYER (%) INSULATINGLAYER (%) 1ST MAGNETIC LAYER (%) NONE 71 64 53 Ti (5 nm) 0 0 0 Ta (5 nm)2 1 1 Cr (5 nm) 7 4 3

[0097] TABLE 11 A case of the first magnetic layer 16 made of Co₇₇Fe₁₉B₄PROBABILITY OF OCCURRENCE PROBABILITY OF OCCURRENCE PROBABILITY OFOCCURRENCE KIND OF 1ST NON- OF STRIPPING IN OF CRACK IN 2ND OF SHAPEANOMALY IN MAGNETIC LAYER 1ST MAGNETIC LAYER (%) INSULATING LAYER (%)1ST MAGNETIC LAYER (%) NONE 75 67 61 Ti (5 nm) 2 1 1 Ta (5 nm) 1 0 0 Cr(5 nm) 7 5 4

[0098] TABLE 12 A case of the first magnetic layer 16 made of Co₉₀Fe₁₀PROBABILITY OF OCCURRENCE PROBABILITY OF OCCURRENCE PROBABILITY OFOCCURRENCE KIND OF 1ST NON- OF STRIPPING IN OF CRACK IN 2ND OF SHAPEANOMALY IN MAGNETIC LAYER 1ST MAGNETIC LAYER (%) INSULATING LAYER (%)1ST MAGNETIC LAYER (%) NONE 66 58 55 Ti (5 nm) 1 0 0 Ta (5 nm) 1 0 0 Cr(5 nm) 4 2 2

[0099] In each case of Co₇₄Fe₂₃Cu₃, Co₇₂Fe₂₄MO₄, Co₇₇Fe₁₉B₄, andCo₉₀Fe₁₀, the probability of occurrence of wrong has 50% to 70% level ina case of using no fist non-magnetic layer 22 and is high probability ofoccurrence of wrong although it is not high in comparison with a case ofthe above-mentioned two-layer film made of nickel-iron(NiFe)/cobalt-iron-nickel (CoFeNi) or the above-mentioned single-layerfilm made of cobalt-nickel-iron (CoNiFe). However, by using, as thefirst non-magnetic layer 22, a lamina made of metal selected fromtitanium (Ti), tantalum (Ta), and chromium (Cr) of a thickness of 5 nmin any case, the probability of occurrence of wrong is lowered toseveral % or less. It is understood that the first non-magnetic layer 22made of metal selected from titanium (Ti), tantalum (Ta) ,and chromium(Cr) has the wrong occurrence resist effect not only in the two-layerfilm made of nickel-iron (NiFe)/cobalt-iron-nickel (CoFeNi) or thesingle-layer film made of cobalt-iron-nickel (CoFeNi) but also in usingany one of cobalt-iron-copper (CoFeCu), cobalt-iron-molybdenum (CoFeMo),cobalt-iron-boron (CoFeB), and cobalt-iron (CoFe).

[0100] Although examination is now not made, it seems that it hassimilar effect in a case of a multi-layer film obtained by combiningnickel-iron (NiFe) with any one of cobalt-iron-copper (CoFeCu),cobalt-iron-molybdenum (CoFeMo), cobalt-iron-boron (CoFeB), orcobalt-iron (CoFe).

[0101] Tables 13, 14, 15, and 16 show probability of occurrence ofstripping in the second magnetic layer 21, probability of occurrence ofcrack in the second insulating layer 20, and probability of occurrenceof shape anomaly in the second magnetic layer 21 in a case ofmanufacturing the magnetic head having structure illustrated in FIGS. 3and 4 by using, as the second non-magnetic layer 24, a lamina made ofmetal selected from titanium (Ti), tantalum (Ta), and chromium (Cr) eachhaving a thickness of 30 nm and by using, as the second magnetic layer21, a single-layer film made of one selected from Co₇₄Fe₂₃Cu₃,Co₇₂Fe₂₄Mo₄, Co₇₇Fe₁₉B₄, and Co₉₀Fe₁₀, respectively, each of which has athickness of 1.4 μm and each of which is formed by plating with using nostress relaxation agent. In elements used in measurement, the firstmagnetic layer 16 comprises a single-layer film made of Co₆₅Fe₂₃Ni₁₂(2.0 μm) formed by plating with using no stress relaxation agent. Inorder to resist wrong occurrence caused by the first magnetic layer 16,the first non-magnetic layer 22 made of titanium (Ti) having a thicknessof 5 nm. As result, wrong such as stripping caused by the first magneticlayer 16, occurrence of crack, and shape anomaly is not occurred. Aseach element of the magnetic head, similar ones used in those to obtaindata in Tables 1 to 3 are used. TABLE 13 A case of the second magneticlayer 21 made of Co₇₄Fe₂₃Cu₃ PROBABILITY OF OCCURRENCE PROBABILITY OFOCCURRENCE PROBABILITY OF OCCURRENCE KIND OF 2ND NON- OF STRIPPING IN OFCRACK IN 2ND OF SHAPE ANOMALY IN MAGNETIC LAYER 2ND MAGNETIC LAYER (%)INSULATING LAYER (%) 2ND MAGNETIC LAYER (%) NONE 78 65 61 Ti (30 nm) 0 00 Ta (30 nm) 0 0 0 Cr (30 nm) 2 2 1

[0102] TABLE 14 A case of the second magnetic layer 21 made ofCo₇₂Fe₂₄Mo₄ PROBABILITY OF OCCURRENCE PROBABILITY OF OCCURRENCEPROBABILITY OF OCCURRENCE KIND OF 2ND NON- OF STRIPPING IN OF CRACK IN2ND OF SHAPE ANOMALY IN MAGNETIC LAYER 2ND MAGNETIC LAYER (%) INSULATINGLAYER (%) 2ND MAGNETIC LAYER (%) NONE 74 63 54 Ti (30 nm) 2 2 1 Ta (30nm) 0 0 0 Cr (30 nm) 9 8 6

[0103] TABLE 15 A case of the second magnetic layer 21 made ofCo₇₇Fe₁₉B₄ PROBABILITY OF OCCURRENCE PROBABILITY OF OCCURRENCEPROBABILITY OF OCCURRENCE KIND OF 2ND NON- OF STRIPPING IN OF CRACK IN2ND OF SHAPE ANOMALY IN MAGNETIC LAYER 2ND MAGNETIC LAYER (%) INSULATINGLAYER (%) 2ND MAGNETIC LAYER (%) NONE 73 64 59 Ti (30 nm) 2 2 1 Ta (30nm) 1 1 0 Cr (30 nm) 3 2 1

[0104] TABLE 16 A case of the second magnetic layer 21 made of Co₉₀Fe₁₀PROBABILITY OF OCCURRENCE PROBABILITY OF OCCURRENCE PROBABILITY OFOCCURRENCE KIND OF 2ND NON- OF STRIPPING IN OF CRACK IN 2ND OF SHAPEANOMALY IN MAGNETIC LAYER 2ND MAGNETIC LAYER (%) INSULATING LAYER (%)2ND MAGNETIC LAYER (%) NONE 68 61 56 Ti (30 nm) 1 1 0 Ta (30 nm) 1 0 0Cr (30 nm) 2 1 0

[0105] In each case of Co₇₄Fe₂₃Cu₃, Co₇₂Fe₂₄MO₄, Co₇₇Fe₁₉B₄, andCo₉₀Fe₁₀, the probability of occurrence of wrong has 50% to 70% level ina case of using no second non-magnetic layer 24 and is high probabilityof occurrence of wrong although it is not high in comparison with a caseof the above-mentioned two-layer film made of nickel-iron(NiFe)/cobalt-iron-nickel (CoFeNi) or the above-mentioned single-layerfilm made of cobalt-nickel-iron (CoNiFe). However, by using, as thesecond non-magnetic layer 24, a lamina made of metal selected fromtitanium (Ti), tantalum (Ta), and chromium (Cr) of a thickness of 30 nmin any case, the probability of occurrence of wrong is lowered toseveral % or less. It is understood that the second non-magnetic layer24 is made of one selected from titanium (Ti), tantalum (Ta) andchromium (Cr) has the wrong occurrence resist effect not only in thetwo-layer film made of nickel-iron (NiFe)/cobalt-iron-nickel (CoFeNi) orthe single-layer film made of cobalt-iron-nickel (CoFeNi) but also inusing any one of cobalt-iron-copper (CoFeCu), cobalt-iron-molybdenum(CoFeMo), cobalt-iron-boron (CoFeB), and cobalt-iron (CoFe).

[0106] Although examination is now not made, it seems that it hassimilar effect in a case of a multi-layer film obtained by combiningnickel-iron (NiFe) with any one of cobalt-iron-copper (CoFeCu) ,cobalt-iron-molybdenum (CoFeMo), cobalt-iron-boron (CoFeB), orcobalt-iron (CoFe).

[0107] It is thought that there are two effects as the wrong resisteffect in the first non-magnetic layer 22 and in the second non-magneticlayer 24. A first effect is an effect to improve adhesion between themagnetic separation layer 13 and the first conductive layer 23 orbetween the second insulating layer 20 and the second conductive layer25 because the first non-magnetic layer 22 lies between the magneticseparation layer 13 and the first conductive layer 23 or the secondnon-magnetic layer 24 lies between the second insulating layer 20 andthe second conductive layer 25. A second effect is an effect to reducestress in the first conductive layer 23/the first magnetic layer 16 orin the second conductive layer 25/the second magnetic layer 21 becausethe first nonmagnetic layer 22 is adjacent to the first conductive layer23/the first magnetic layer 16 or the second non-magnetic layer 24 isadjacent to the second conductive layer 25/the second magnetic layer 21.

[0108] Sixthly, examination is made about whether the wrong occurrenceresist effect is caused by an adhesion improvement effect or a stressreduction effect.

[0109] At first, the present co-inventors examined how large is theadhesion improvement effect by using the non-magnetic layer. A laminamade of metal selected from titanium (Ti), tantalum (Ta), and chromium(Cr) having a thickness of 10 nm is formed on a glass substrate as anon-magnetic layer by sputtering, a layer made of Ni₈₀Fe₂₀ having athickness of 100 nm is formed on the non-magnetic layer as a conductivelayer by sputtering, and a layer made of Co₆₅Fe₂₃Ni₁₂ having a thicknessof 2 μm is formed on the conductive layer as a magnetic layer by platingusing a stress relaxation agent. In order to make a comparison, a samplewith no non-magnetic layer is made. A reason that the stress relaxationagent is used on making the magnetic layer by plating which is differentfrom an actual process is that stripping of the magnetic layer instantlyoccurs in a case that the non-magnetic layer is not formed if the stressrelaxation agent is not used and it is therefor impossible to measureadhesion of a compared sample.

[0110] For each of four samples made in the above-mentioned manner,adhesion is measured by using an acoustic emission method. The acousticemission method is a method comprising the steps of applying warp stressto a substrate on which a stress measured film is formed and ofdetecting, as adhesion, a stress at which separation occurs by detectingthe separation of the film from the substrate by sound. Although theseparation of the film caused by applying of the stress occurs in awidth of a level of stress, the adhesion is herein defined as the stresswhen the separation occurs most frequently. The adhesion in this case isshown in Table 17. TABLE 17 ADHESION (GPa) No non-magnetic layer 9 Ti(10 nm) 58 Ta (10 nm) 62 Cr (10 nm) 41

[0111] In a case of using no non-magnetic layer, the adhesion is 9 GPaand is small. In comparison with this, in a case of using a lamina madeof metal selected from titanium (Ti), tantalum (Ta), and chromium (Cr)as the non-magnetic layer, the adhesion is drastically large. Amongthree types of the non-magnetic layer, the adhesion is about same levelin titanium (Ti) and tantalum (Ta) and the adhesion in chromium (Cr) issmaller than that by little.

[0112] Although a portion corresponding to the substrate in thisexperimentation is made of a material except for the glass such as themagnetic separation layer 13 or the second insulating layer 20, it seemsthat the adhesion improvement effect caused by presence of thenon-magnetic layer is present in such a case.

[0113] Subsequently, the present co-inventors examines the stressreduction effect caused by use of the non-magnetic layer. A lamina madeof metal selected from titanium (Ti), tantalum (Ta), and chromium (Cr)having a thickness of 10 nm is formed on a substrate having a knownamount of warp as a non-magnetic layer by sputtering, a layer made ofNi₈₀Fe₂₀ having a thickness of 100 nm is formed on the non-magneticlayer as a conductive layer by sputtering, and a layer made ofCo₆₅Fe₂₃Ni₁₂ having a thickness of 0.3 μm is formed on the conductivelayer as a magnetic layer by plating with no stress relaxation agent. Inorder to make a comparison, a sample with no non-magnetic layer isformed. A reason that the magnetic layer has a thin thickness to 0.3 μmwhich is different from an actual process is that separation of themagnetic immediately occurs in a case of forming no non-magnetic layerif a thickness of the magnetic layer is thick and it is thereforeimpossible to measure the adhesion of a compared sample.

[0114] For four types of samples made in the manner which is describedabove, the amount of warp in a Si substrate is measured to calculatestress in the layer. Measured results are shown Table 18. TABLE 18INTERNAL STRESS (MPa) No non-magnetic layer 2560 Ti (10 nm) 1250 Ta (10nm) 900 Cr (10 nm) 750

[0115] In a case of using no nonmagnetic layer, the interval stress isequal to 2560MPa and is large. In comparison with this, in a case ofusing a lamina made of metal selected from titanium (Ti), tantalum (Ta),and chromium (Cr) as the non-magnetic layer, the internal stress isdrastically decreased. It seems that titanium (Ti) and tantalum (Ta)have an effect so as to decrease the internal stress in acobalt-iron-nickel (CoFeNi) plating layer formed thereon. Among threetypes of non-magnetic layers, the internal stress becomes small in orderto titanium (Ti), tantalum (Ta), and chromium (Cr).

[0116] In the manner in the actual magnetic head as understood from thatthere is a little wrong occurrence in chromium (Cr) in comparison withthat there is no wrong occurrence in tantalum (Ta) and titanium (Ti)when the first non-magnetic layer has a thickness of 4 nm in a case ofcomparing, for example, Tables 1, 2, and 3, it tends to have a largerwrong occurrence resist effect in a case of using a lamina made of metalselected from tantalum (Ta) and titanium (Ti) as the first and thesecond non-magnetic layers 22 and 24 in comparison with a case of usinga lamina made of chromium (Cr) as the first and the second non-magneticlayers 22 and 24. Although, from Table 18, titanium (Ti) and tantalum(Ta) have a smaller stress reduction effect in comparison with chromium(Cr), titanium (Ti) and tantalum (Ta) have a larger adhesion improvementeffect in comparison with chromium (Cr) in the manner which isunderstood from Table 17. As a result of addition of the two effects, itseems that titanium (Ti) and tantalum (Ta) have an excellent wrongoccurrence resist effect more than chromium (Cr).

[0117] In addition, the present co-inventors considered that it seemsthat one of reasons for reduction of the stress in the magnetic layer byusing a film made of one selected from titanium (Ti), tantalum (Ta), andchromium (Cr) as the non-magnetic layer may be an effect caused byaddition of stresses in the non-magnetic layer, in the conductive layer,and in the magnetic layer. In order to check this, the presentco-inventors measured stress in a single-layer film made of metalselected from titanium (Ti), tantalum (Ta), and chromium (Cr). Table 19shows internal stress in the single-layer film made of metal selectedfrom titanium (Ti), tantalum (Ta), and chromium (Cr) in a case where itsthickness is equal to 50 nm. TABLE 19 INTENAL STRESS (MPa) Ti (50 nm)−210 Ta (50 nm) −530 Cr (50 nm) −420

[0118] In a case of each of titanium (Ti) , tantalum (Ta), and chromium(Cr) , the internal stress has a negative (minus) value Accordingly, ina total of the non-magnetic layer, the conductive layer, and themagnetic layer, it is anticipated that a total stress value obtained byadding respective stress values may become smaller in each case thanthat in a case of no non-magnetic layer and matches with a tendency ofthe results shown in Table 18. While negative stress values in thesingle-layer film are, in descending order, tantalum (Ta), chromium(Cr), and titanium (Ti), namely,

[0119] Ta>Cr>Ti,

[0120] total stress values in the non-magnetic layer, the conductivelayer, and the magnetic layer are, in descending order, titanium (Ti),tantalum (Ta), and chromium (Cr), namely,

[0121] Ti>Ta>Cr.

[0122] Accordingly, larger ones of the negative stress in thesingle-layer film are not always smaller ones of the total stressvalues. This means that a reason that the non-magnetic layer can reducethe stress of the magnetic layer is not always that the negative stressin the single-layer of the non-magnetic layer is merely added. A futureproblem is to examine what is this reason

[0123] It is understood that to use, as the non-magnetic layer, amaterial (metal) having the negative stress value has an effect onreduction of the total stress value as shown in data of Tables 18 and19. Accordingly, the stress relaxation effect for the magnetic layer maybe expected in a case of using, as the non-magnetic layer, asingle-layer film made of a material (metal) having the negative stressalthough the material (metal) is a material (metal) except for titanium(Ti), tantalum (Ta), and chromium (Cr). Thereupon, as regards severaltypes of material (metal), the present co-inventors formed asingle-layer film having a thickness of 50 nm on a glass substrate andmeasured stress of the single-layer film. As regards the materials(metals) having the negative stress value there among, the presentco-inventors measured adhesion of the single-layer film having thethickness of 50 nm formed on the glass substrate using an acousticemission method and obtained measured values shown in Table 20. TABLE 20TYPE OF INTERNAL STRESS MATERAL (MPa) ADHESION (GPa) Y −350 32 Zr −32033 Hf −230 34 V −390 38 Nb −280 36 Mo −370 31 W −280 36 Mn −220 2 Re−150 1

[0124] In a case of any material, an effect for reducing a total stressin the magnetic layer may be expected because any material (metal) hasthe internal stress of a negative value. However, inasmuch as manganese(Mn) and rhenium (Re) have the adhesion less than 10GPa although itsfilm is formed on a clean glass substrate, the wrong occurrence resisteffect cannot be expected in a state where the magnetic head is actuallymanufactured. Inasmuch as yttrium (Y), zirconium (Zr), hafnium (Hf),vanadium (V), niobium (Nb), molybdenum (Mo), and wolfram (tungsten) (W)have adhesion of a level of 30GPa although its adhesion is not higherthan that in titanium (Ti), tantalum (Ta), and chromium (Cr), they arelikely candidates of the material (metal) for the first and the secondnon-magnetic layers 22 and 24 if they are excellent in corrosionresistance and in compatibility of a head manufacturing process.

[0125] While this invention has thus far been described in conjunctionwith few preferred embodiments thereof, it will now be readily possiblefor those skilled in the art to put this invention into various othermanners. For example, the magnetic layer (first magnetic sub-layer)comprising the essential elements of cobalt (Co), nickel (Ni), and iron(Fe) may have a crystal structure selected from the group consisting ofa face-centered cubic (fcc) structure, a body-centered cubic (bcc)structure, and a mixed crystal with a face-centered cubic (fcc)structure and a body-centered cubic (bcc) structure. The magnetic layer(first magnetic sub-layer) comprising the essential elements of cobalt(Co), nickel (Ni) and iron (Fe) may have a crystal particle diameterwhich is not more than 20 .

What is claimed is:
 1. A magnetic head comprising: a substrate having aprincipal surface; an antistripping layer formed on the principalsurface of said substrate; a first magnetic layer formed on saidantistripping layer; a recording gap layer formed on said first magneticlayer; an insulating layer formed on said recording gap layer except fora pole tip region; a write coil enclosed with and insulated by saidinsulating layer; and a second magnetic layer formed on said insulatinglayer and on the pole tip region of said recording gap layer.
 2. Amagnetic head as claimed in claim 1, wherein said antistripping layercomprises: a non-magnetic layer formed on the principal surface of saidsubstrate; and a conductive layer formed on said non-magnetic layer,said first magnetic layer being formed on said conductive layer.
 3. Amagnetic head as claimed in claim 2, wherein said non-magnetic layercomprises a lamina made of metal selected from the group consistingessentially of titanium (Ti), tantalum (Ta), chromium (Cr), yttrium (Y),zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), molybdenum(Mo), and tungsten (W).
 4. A magnetic head as claimed in claim 3,wherein said lamina comprises one selected from a single-layer film, amulti-layer film, and an alloy film.
 5. A magnetic head as claimed inclaim 2, wherein said non-magnetic layer is made of a non-magneticmaterial of titanium (Ti), said non-magnetic layer having a thicknessbetween 2 nm and 10 nm, both inclusive.
 6. A magnetic head as claimed inclaim 2, wherein said non-magnetic layer is made of a non-magneticmaterial of tantalum (Ta), said non-magnetic layer having a thicknessbetween 1.5 nm and 10 nm, both inclusive.
 7. A magnetic head as claimedin claim 2, wherein said non-magnetic layer is made of a nonmagneticmaterial of chromium (Cr), said non-magnetic layer having a thicknessbetween 2.5 nm and 10 nm, both inclusive.
 8. A magnetic head as claimedin claim 2, wherein said non-magnetic layer comprises a lamina made ofmetal having a tensile stress.
 9. A magnetic head as claimed in claim 8,wherein said lamina comprises one selected from a single-layer film, amulti-layer film, and an alloy film.
 10. A magnetic head as claimed inclaim 1, wherein said first magnetic layers comprise a lamina selectedfrom the group consisting essentially of cobalt-iron-nickel (CoFeNi),cobalt-iron-copper (CoFeCu), cobalt-iron-molybdenum (CoFeMo),cobalt-iron-boron (CoFeB), and cobalt-iron (CoFe).
 11. A magnetic headas claimed in claim 10, wherein said lamina comprises alloy.
 12. Amagnetic head as claimed in claim 10, wherein said lamina comprises oneselected from a single-layer film and a multi-layer film.
 13. A magnetichead as claimed in claim 10, wherein said lamina comprises a mixture.14. A magnetic head as claimed in claim 13, wherein said mixture furthercomprises an additional alloy consisting essentially of nickel-iron(NiFe).
 15. A magnetic head as claimed in claim 1, wherein said firstmagnetic layer comprises essential elements of cobalt (Co), nickel (Ni),and iron (Fe)
 16. A magnetic head as claimed in claim 1, wherein saidfirst magnetic layer comprises a laminated structure of a first magneticsub-layer comprising essential elements of cobalt (Co), nickel (Ni), andiron (Fe) and a second magnetic sub-layer comprising essential elementsof nickel (Ni) and iron (Fe), said first magnetic sub-layer beingdisposed near to said recording gap layer.
 17. A magnetic head asclaimed in claim 15, wherein said first magnetic layer has a crystalstructure of a face-centered cubic (fcc) structure.
 18. A magnetic headas claimed in claim 15, wherein said first magnetic layer has a crystalstructure of a body-centered cubic (bcc) structure.
 19. A magnetic headas claimed in claim 15, wherein said first magnetic layer has a crystalstructure of a mixed crystal with a face-centered cubic (fcc) structureand a body-centered cubic (bcc) structure.
 20. A magnetic head asclaimed in claim 16, wherein said first magnetic sub-layer has a crystalstructure of a face-centered cubic (fcc) structure.
 21. A magnetic headas claimed in claim 16, wherein said first magnetic sub-layer has acrystal structure of a body-centered cubic (bcc) structure.
 22. Amagnetic head as claimed in claim 16, wherein said first magneticsub-layer has a crystal structure of a mixed crystal with aface-centered cubic (fcc) structure and a body-centered cubic (bcc)structure.
 23. A magnetic head as claimed in claim 15, wherein saidfirst magnetic layer has a crystal particle diameter which is not morethan 20 nm.
 24. A magnetic head as claimed in claim 16, wherein saidfirst magnetic sub-layer has a crystal particle diameter which is notmore than 20 nm.
 25. A magnetic head as claimed in claim 1, wherein acombination of said insulating layer and said write coil is made bysuccessively laminating a first insulating layer, said write coil, and asecond insulating layer on said recording gap layer, said secondinsulating layer having a periphery end on a side of an air bearingsurface (ABS) that is close to said air bearing surface than a peripheryend of said first insulating layer.
 26. A magnetic head as claimed inclaim 1, wherein said substrate comprises: an insulating substratehaving a principal surface; a first magnetic shield layer formed on theprincipal surface of said insulating substrate; a magnetic separationlayer formed on said first magnetic shield layer, said magneticseparation layer being made of an insulator; and a magneto-resistiveeffective element sandwiched in said magnetic separation layer, saidantistripping layer being formed on said magnetic separation layer, saidfirst magnetic layer doubling as a second magnetic shield layer.
 27. Aprocess for manufacturing a magnetic head as claimed in claim 1, whereinsaid first magnetic layers is made by electroplating.
 28. A process formanufacturing a magnetic head as claimed in claim 15, wherein said firstmagnetic layer is made by electroplating.
 29. A process formanufacturing a magnetic head as claimed in claim 16, wherein said firstmagnetic sub-layer is made by electroplating.
 30. A process formanufacturing a magnetic head as claimed in claim 15, wherein said firstmagnetic layer is made by electroplating with a plating bath includingno stress relieving agent.
 31. A process for manufacturing a magnetichead as claimed in claim 16, wherein said first magnetic sub-layer ismade by electroplating with a plating bath including no stress relievingagent.
 32. A magnetic storage unit comprising a magnetic head as claimedin claim 1 and a magnetic recording medium which has a coercive force of278600 A/m or more and which has a recording density of 10gigabits/inch² or more.
 33. A magnetic storage unit comprising amagnetic head as claimed in claim 2 and a magnetic recording mediumwhich has a coercive force of 278600 A/m or more and which has arecording density of 10 gigabits/inch² or more.
 34. A magnetic storageunit comprising a magnetic head as claimed in claim 15 and a magneticrecording medium which has a coercive force of 278600 A/m or more andwhich has a recording density of 10 gigabits/inch² or more.
 35. Amagnetic storage unit comprising a magnetic head as claimed in claim 25and a magnetic recording medium which has a coercive force of 278600 A/mor more and which has a recording density of 10 gigabits/inch² or more.36. A magnetic storage unit comprising a magnetic head as claimed inclaim 26 and a magnetic recording medium which has a coercive force of278600 A/m or more and which has a recording density of 10gigabits/inch² or more.
 37. A magnetic head comprising: a substratehaving a principal surface; a first magnetic layer formed on saidsubstrate; a recording gap layer formed on said first magnetic layer; aninsulating layer formed on said recording gap layer except for a poletip region; a write coil enclosed with and insulated by said insulatinglayer; an antistripping layer formed on said insulating layer and on thepole tip region of said recording gap layer; and a second magnetic layerformed on said antistripping layer.
 38. A magnetic head as claimed inclaim 37, wherein said antistripping layer comprises: a non-magneticlayer formed on said insulating layer and on the pole tip region of saidrecording gap layer; and a conductive layer formed on said non-magneticlayer, said second magnetic layer being formed on said conductive layer.39. A magnetic head as claimed in claim 38, wherein said non-magneticlayer a lamina made of metal selected from the group consistingessentially of titanium (Ti), tantalum (Ta), chromium (Cr), yttrium (Y),zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), molybdenum(Mo), and tungsten (W).
 40. A magnetic head as claimed in claim 39,wherein said lamina comprises one selected from a single-layer film, amulti-layer film, and an alloy film.
 41. A magnetic head as claimed inclaim 38, wherein said non-magnetic layer is made of a non-magneticmaterial of titanium (Ti), said non-magnetic layer having a thicknessbetween 10 nm and 290 nm, both inclusive.
 42. A magnetic head as claimedin claim 38, wherein said nonmagnetic layer is made of a non-magneticmaterial of tantalum (Ta), said non-magnetic layer having a thicknessbetween 8 nm and 290 nm, both inclusive.
 43. A magnetic head as claimedin claim 38, wherein said non-magnetic layer is made of a non-magneticmaterial of chromium (Cr), said non-magnetic layer having a thicknessbetween 12 nm and 290 nm, both inclusive.
 44. A magnetic head as claimedin claim 38, wherein said non-magnetic layer comprises a lamina made ofmetal having a tensile stress.
 45. A magnetic head as claimed in claim44, wherein said lamina comprises one selected from a single-layer film,a multi-layer film, and an alloy film.
 46. A magnetic head as claimed inclaim 37, wherein said first magnetic layers comprise a lamina selectedfrom the group consisting essentially of cobalt-iron-nickel (CoFeNi),cobalt-iron-copper (CoFeCu) ,cobalt-iron-molybdenum (CoFeMo),cobalt-iron-boron (CoFeB), and cobalt-iron (CoFe).
 47. A magnetic headas claimed in claim 46, wherein said lamina comprises alloy.
 48. Amagnetic head as claimed in claim 46, wherein said lamina comprises oneselected from a single-layer film and a multi-layer film.
 49. A magnetichead as claimed in claim 46, wherein said lamina comprises a mixture.50. A magnetic head as claimed in claim 49, wherein said mixture furthercomprises an additional alloy consisting essentially of nickel-iron(NiFe).
 51. A magnetic head as claimed in claim 37, wherein said secondmagnetic layer comprises essential elements of cobalt (Co), nickel (Ni),and iron (Fe).
 52. A magnetic head as claimed in claim 37, wherein saidsecond magnetic layer comprises a laminated structure of a firstmagnetic sub-layer comprising essential elements of cobalt (Co), nickel(Ni), and iron (Fe) and a second magnetic sub-layer comprising essentialelements of nickel (Ni) and iron (Fe), said first magnetic sub-layerbeing disposed near to said recording gap layer.
 53. A magnetic head asclaimed in claim 51, wherein said second magnetic layer has a crystalstructure of a face-centered cubic (fcc) structure.
 54. A magnetic headas claimed in claim 51, wherein said second magnetic layer has a crystalstructure of a body-centered cubic (bcc) structure.
 55. A magnetic headas claimed in claim 51, wherein said second magnetic layer has a crystalstructure of a mixed crystal with a face-centered cubic (fcc) structureand a body-centered cubic (bcc) structure.
 56. A magnetic head asclaimed in claim 52, wherein said first magnetic sub-layer has a crystalstructure of a face-centered cubic (fcc) structure.
 57. A magnetic headas claimed in claim 52, wherein said first magnetic su-layer has acrystal structure of a body-centered cubic (bcc) structure.
 58. Amagnetic head as claimed in claim 52, wherein said first magneticsub-layer has a crystal structure of a mixed crystal with aface-centered cubic (fcc) structure and a body-centered cubic (bcc)structure.
 59. A magnetic head as claimed in claim 51, wherein saidsecond magnetic layer has a crystal particle diameter which is not morethan 20 nm.
 60. A magnetic head as claimed in claim 52, wherein saidfirst magnetic sub-layer has a crystal particle diameter which is notmore than 20 nm.
 61. A magnetic head as claimed in claim 37, wherein acombination of said insulating layer and said write coil is made bysuccessively laminating a first insulating layer, said write coil, and asecond insulating layer on said recording gap layer, said secondinsulating layer having a periphery end on a side of an air bearingsurface (ABS) that is close to said air bearing surface than a peripheryend of said first insulating layer.
 62. A magnetic head as claimed inclaim 37, wherein said substrate comprises: an insulating substratehaving a principal surface; a first magnetic shield layer formed on theprincipal surface of said insulating substrate; a magnetic separationlayer formed on said first magnetic shield layer, said magneticseparation layer being made of an insulator; and a magneto-resistiveeffective element sandwiched in said magnetic separation layer, saidfirst magnetic layer being formed on said magnetic separation layer,said first magnetic layer doubling as a second magnetic shield layer.63. A process for manufacturing a magnetic head as claimed in claim 37,wherein said second magnetic layer is made by electroplating.
 64. Aprocess for manufacturing a magnetic head as claimed in claim 51,wherein said second magnetic layer is made by electroplating.
 65. Aprocess for manufacturing a magnetic head as claimed in claim 52,wherein said first magnetic sub-layer is made by electroplating.
 66. Aprocess for manufacturing a magnetic head as claimed in claim 51,wherein said second magnetic layer is made by electroplating with aplating bath including no stress relieving agent.
 67. A process formanufacturing a magnetic head as claimed in claim 52, wherein said firstmagnetic sub-layer is made by electroplating with a plating bathincluding no stress relieving agent.
 68. A magnetic storage unitcomprising a magnetic head as claimed in claim 37 and a magneticrecording medium which has a coercive force of 278600 A/m or more andwhich has a recording density of 10 gigabits/inch² or more.
 69. Amagnetic storage unit comprising a magnetic head as claimed in claim 38and a magnetic recording medium which has a coercive force of 278600 A/mor more and which has a recording density of 10 gigabits/inch² or more.70. A magnetic storage unit comprising a magnetic head as claimed inclaim 51 and a magnetic recording medium which has a coercive force of278600 A/m or more and which has a recording density of 10gigabits/inch² or more.
 71. A magnetic storage unit comprising amagnetic head as claimed in claim 61 and a magnetic recording mediumwhich has a coercive force of 278600 A/m or more and which has arecording density of 10 gigabits/inch² or more.
 72. A magnetic storageunit comprising a magnetic head as claimed in claim 62 and a magneticrecording medium which has a coercive force of 278600 A/m or more andwhich has a recording density of 10 gigabits/inch² or more.
 73. Amagnetic head comprising: a substrate having a principal surface; afirst antistripping layer formed on the principal surface of saidsubstrate; a first magnetic layer formed on said first antistrippinglayer; a recording gap layer formed on said first magnetic layer; aninsulating layer formed on said recording gap layer except for a poletip region; a write coil enclosed with and insulated by said insulatinglayer; a second antistripping layer formed on said insulating layer andon the pole tip region of said recording gap layer; and a secondmagnetic layer formed on said second antistripping layer.
 74. A magnetichead as claimed in claim 73, wherein said first antistripping layercomprises: a first non-magnetic layer formed an the principal surface ofsaid substrate; and a first conductive layer formed on said firstnon-magnetic layer, said first magnetic layer being formed on said firstconductive layer, said second antistripping layer comprising: a secondnon-magnetic layer formed on said insulating layer and on the pole tipregion of said recording gap layer; and a second conductive layer formedon said second non-magnetic layer, said second magnetic layer beingformed on said second conductive layer.
 75. A magnetic head as claimedin claim 74, wherein each of said first and said second non-magneticlayers comprises a lamina made of metal selected from the groupconsisting of titanium (Ti), tantalum (Ta), chromium (Cr), yttrium (Y),zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), molybdenum(Mo), and tungsten (W).
 76. A magnetic head as claimed in claim 75,wherein said lamina comprises one selected from a single-layer film, amulti-layer film, and an alloy film.
 77. A magnetic head as claimed inclaim 73, wherein each of said first and said second non-magnetic layersis made of a non-magnetic material of titanium (Ti), said firstnon-magnetic layer having a thickness between 2 nm and 10 nm, bothinclusive, said second non-magnetic layer having a thickness between 10nm and 290 nm, both inclusive.
 78. A magnetic head as claimed in claim73, wherein each of said first and said second non-magnetic layers ismade of a non-magnetic material of tantalum (Ta) , said firstnon-magnetic layer having a thickness between 1.5 nm and 10 nm, bothinclusive, said second non-magnetic layer having a thickness between 8nm and 290 nm, both inclusive.
 79. A magnetic head as claimed in claim73, wherein each of said first and said second non-magnetic layers ismade of a non-magnetic material of chromium (Cr), said firstnon-magnetic layer having a thickness between 2.5 nm and 10 nm, bothinclusive, said second non-magnetic layer having a thickness between 12nm and 290 nm, both inclusive.
 80. A magnetic head as claimed in claim74, wherein each of said first and said second non-magnetic layerscomprises a lamina made of metal having a tensile stress.
 81. A magnetichead as claimed in claim 80, wherein said lamina comprises one selectedfrom a single-layer film, a multi-layer film, and an alloy film.
 82. Amagnetic head as claimed in claim 73, wherein each of said first andsaid second magnetic layers comprises a lamina selected from the groupconsisting essentially of cobalt-iron-nickel (CoFeNi) ,cobalt-iron-copper (CoFeCu), cobalt-iron-molybdenum (CoFeMo),cobalt-iron-boron (CoFeB), and cobalt-iron (CoFe).
 83. A magnetic headas claimed in claim 82, wherein said lamina comprises alloy.
 84. Amagnetic head as claimed in claim 82, wherein said lamina comprises oneselected from a single-layer film and a multi-layer film.
 85. A magnetichead as claimed in claim 82, wherein said lamina comprises a mixture.86. A magnetic head as claimed in claim 85, wherein said mixture furthercomprises an additional alloy consisting essentially of nickel-iron(NiFe).
 87. A magnetic head as claimed in claim 73, wherein each of saidfirst and said second magnetic layers comprises essential elements ofcobalt (Co), nickel (Ni), and iron (Fe).
 88. A magnetic head as claimedin claim 73, wherein each of said first and said second magnetic layerscomprises a laminated structure of a first magnetic sub-layer comprisingessential elements of cobalt (Co), nickel (Ni), and iron (Fe) and asecond magnetic sub-layer comprising essential elements of nickel (Ni)and iron (Fe), said first magnetic sub-layer being disposed near to saidrecording gap layer.
 89. A magnetic head as claimed in claim 87, whereineach of said first and said second magnetic layers has a crystalstructure of a face-centered cubic (fcc) structure.
 90. A magnetic headas claimed in claim 87, wherein each of said first and said secondmagnetic layers has a crystal structure of a body-centered cubic (bcc)structure.
 91. A magnetic head as claimed in claim 87, wherein each ofsaid first and said second magnetic layers has a crystal structure of amixed crystal with a face-centered cubic (fcc) structure and abody-centered cubic (bcc) structure.
 92. A magnetic head as claimed inclaim 88, wherein said first magnetic sub-layer has a crystal structureof a face-centered cubic (fcc) structure.
 93. A magnetic head as claimedin claim 88, wherein said first magnetic sub-layer has a crystalstructure of a body-centered cubic (bcc) structure.
 94. A magnetic headas claimed in claim 88, wherein said first magnetic sub-layer has acrystal structure of a mixed crystal with a face-centered cubic (fcc)structure and a body-centered cubic (bcc) structure.
 95. A magnetic headas claimed in claim 87, wherein each of said first and said secondmagnetic layers has a crystal particle diameter which is not more than20 nm.
 96. A magnetic head as claimed in claim 88, wherein said firstmagnetic sub-layer has a crystal particle diameter which is not morethan 20 nm.
 97. A magnetic head as claimed in claim 73, wherein acombination of said insulating layer and said write coil is made bysuccessively laminating a first insulating layer, said write coil, and asecond insulating layer on said recording gap layer, said secondinsulating layer having a periphery end on a side of an air bearingsurface (ABS) that is close to said air bearing surface than a peripheryend of said first insulating layer.
 98. A magnetic head as claimed inclaim 73, wherein said substrate comprises: an insulating substratehaving a principal surface; a first magnetic shield layer formed on theprincipal surface of said insulating substrate; a magnetic separationlayer formed on said first magnetic shield layer, said magneticseparation layer being made of an insulator; and a magneto-resistiveeffective element sandwiched in said magnetic separation layer, saidfirst antistripping layer being formed on said magnetic separationlayer, said first magnetic layer doubling as a second magnetic shieldlayer.
 99. A process for manufacturing a magnetic head as claimed inclaim 73, wherein each of said first and said second magnetic layers ismade by electroplating.
 100. A process for manufacturing a magnetic headas claimed in claim 87, wherein each of said first and said secondmagnetic layers is made by electroplating.
 101. A process formanufacturing a magnetic head as claimed in claim 88, wherein said firstmagnetic sub-layer is made by electroplating.
 102. A process formanufacturing a magnetic head as claimed in claim 87, wherein each ofsaid first and said second magnetic layers is made by electroplatingwith a plating bath including no stress relieving agent.
 103. A processfor manufacturing a magnetic head as claimed in claim 88, wherein saidfirst magnetic sub-layer is made by electroplating with a plating bathincluding no stress relieving agent.
 104. A magnetic storage unitcomprising a magnetic head as claimed in claim 73 and a magneticrecording medium which has a coercive force of 278600 A/m or more andwhich has a recording density of 10 gigabits/inch² or more.
 105. Amagnetic storage unit comprising a magnetic head as claimed in claim 74and a magnetic recording medium which has a coercive force of 278600 A/mor more and which has a recording density of 10 gigabits/inch² or more.106. A magnetic storage unit comprising a magnetic head as claimed inclaim 87 and a magnetic recording medium which has a coercive force of278600 A/m or more and which has a recording density of 10gigabits/inch² or more.
 107. A magnetic storage unit comprising amagnetic head as claimed in claim 97 and a magnetic recording mediumwhich has a coercive force of 278600 A/m or more and which has arecording density of 10 gigabits/inch² or more.
 108. A magnetic storageunit comprising a magnetic head as claimed in claim 98 and a magneticrecording medium which has a coercive force of 278600 A/m or more andwhich has a recording density of 10 gigabits/inch² or more.